Automatic regulating means for timing devices



Feb. 14, 1939. L v. LUCIA 2,147,376

AUTOMATIC REGULATING MEANS FOR TiMING DEVICES Original Filed Sept. 28,19'54 2 Sheets-Sheet 1 Feb. 14, 1939. I L. v. LUCIA I 2,147,376

AUTOMATIC REGULATING MEANS FOR TIMING DEVI CES Original Filed Sept. 28,1934 2 Sheets-Sheet 2 Patented Feb. 14, 1939 AUTOMATIC REGULA'I'INGMEANS FOR TDIING DEVICES Louis v. Lucia, West ammo, Conn, assignor, bymeme :1 to McGraw Electric Company, Chicago, 111., a corporation ofDelaware Continuation of application No. 745,968,

September 28, 1984.

This application May 3,

1938, Serial N0. 205,817

14 Claim.

This invention relates to automatic regulating means for timing devicessuch as commonly used on toasters, grilles, waflle irons and othersimilar apparatus, and constitutes means for regulating timing devices,for such apparatus, which are of a diiierent type than those describedin connection with my invention set forth in my application, SeriaLNo.508,340, filed January 12, 1931, Patent No. 2,036,178.

The invention claimed in my above mentioned application, is especiallyintended for use in connection with variable speed timing devices of aspecial design, while the instant invention is intended for use inconnection with commonly used timing devices of standard design whichoperate at a constant speed. The purpose of the invention being thesame; namely, to vary the timing period in proportion to the temperatureof the cooking device.

As can be easily understood from the descriptions in my above mentionedapplication, and also in my later application Serial No. 731,480, filedJune 20, 1934, it is especially desirable to regulate the operation ofthe timing device so that the timing period for the cooking operation isvaried to correspond with the variations in temperature in the cookingdevice itself. Where ordinary timing devices are used, the timing periodis constant while the temperature of the cooking device will vary forthe different cooking operations so that, in such cases, the timingperiod will not accurate- 1y correspond with the cooking temperature andtherefore uneven results will be obtained.

While the invention disclosed in the above mentioned applications willaccomplish the desired results by regulating the speed of the timingdevices to correspond with the cooking tempera- .tures, there are anumber of other standard timing devices on the market in which the speedis not variable and consequently my previous invention is not applicablethereto.

It is, therefore, an object of this invention, to provide means wherebysaid timing devices may be regulated to correspond with the temperatureof the cooking device regardless of the speed of the timing device, butby automatically varying the degree to which the said timing devices arewound when their operation is started.

A further object of my invention is to provide means whereby the degreeto which the timing device may be wound preparatory to the operationthereof, is automatically varied to correspond with the actualtemperature withinthe cooking chamber of the cooking device.

A further object is to provide means whereby a predetermined degree oicooking may be obtained regardless of the exact time required and afurther object isto provide means by which either the source oi! heat iscut of! or a signal is given when the predetermined degree of cookinghas been completed.

Further objects oi. my invention may be readily understood from theforegoing descriptionand also from the accompanying drawings in which:

.Figure 1 is a view in central vertical section, on line l-l of Figure2, showing the use of a timing device comprising my invention as appliedto an electric toaster; the timing mechanism not being shown therein.

Figure 2 is a side view of the same in central vertical section; no partoi the timing device other than the winding lever being shown.

Figure 3 is a bottom view of the toaster with the bottom plate thereofremoved.

Figure 4 is a similarwiew showing the application of the same timingdevice to ring a bell.

Figure 5 is a fragmentary view showing my improved regulating means inthe position which it would take when the cooking device is heated.

Figure 6 is a fragmentary view showing a detail of the electric switch.

Figure '1 is a plan view on an enlarged scale of the timing devicecomprising my invention. v

Figure 8 is a similar view showing the same elements in side elevationand showing, in dotted lines, the position of the thermostatic elementwhen heated.

Figure 9 is a plan view of the timing mechanism with some of the partsthereof removed and showing the driving unit in its starting position.

Figure 10 is a view in section on an enlarged scale of a portion showingthe driving unit of the timing mechanism on line Ill-l0 of Figure 9.

In order that the purpose of my invention may be clearly understood tobegin with, I will first describe the application of my invention to anelectric toaster.

As illustrated in the drawings, the numeral 5 denotes the base of anelectric toaster on which is mounted a casing 6. Heating elements i, ofsuitable construction, are supported within the said casing forming acooking chamber 8 between said elements. In the structure shown, thetoaster is constructed so that two slices of bread may be toasted at thesame time and, therefore, three heating elements are used forming twocooking chambers. My invention is applicable either to a single ormultiple slice device.

Bread supports 9 are provided which, as shown, are constructed from amember l0 that is formed to provide a side wall II. A supporting bar 42is secured to this wall and has an upwardly turned portion l3 formingthe opposite side wall of the bread support. Wire guides I4 and I5 areprovided to hold the bread slice in proper relation to the heatingelements. As shown, the said bread supports are hinged as at II in orderthat they may be swung outwardly by grasping a handle l1 and thus movingthe bread slices into or out of said cooking chamber.

Each of the heating elements are constructed of sheets of insulatingmaterial l3 on which is wound an electrical resistance wire l9, whichwire is suitably connected, in a manner well known by those skilled inthe art, to terminal pins 20 which extend within a plug guard 2| and arepositioned to be received by a common electric plug for supply ofcurrentto said elements.

In the device illustrated in Figures 1, 2 and 3 of the drawings, saidresistance wires are connected to said terminals thru an electric switch22 which is located in the base of the toaster.

A timing device 23, of common construction but to which my invention isapplied, is located in the base of said toaster and mounted in a housing24; this timing device is mounted in a frame composed of an upper plate25 and a lower plate 26 and has the usual escapement 21 which is driventhru a train of gears 23 by means of a main driving spring 29 which isconnected to an adjustable driving unit 39. This driving unit as clearlyillustrated in Figure 10 of the drawings comprises a stud 3| which isanchored to the bottom plate 26. On this stud is mounted, over a spacingwasher 32, a winding lever 33 having a handle 34. A main driving spring29 is anchored to the stud 3| as at 35 and the outer end of said springis secured to the winding lever by means of a stud 36. A pawl 31. (seeFigure 9) is pivotally mounted to one end of the winding lever on a post33 and resiliently forced in one direction by means of a spring 39. Areleasing cam .49 is rotatably mounted on the stud 3| and frictionallyheld in fixed position thereon by means of friction discs 4| and 42. Thesaid cam has an adjusting handle 43 extending therefrom by means ofwhich the cam may be selectively positioned. A spindle 44 is rotatablymounted on the axis of the stud 3| and between the said stud and theplate 26. A hub 45 is secured to said spindle and a driving ratchet 46is secured to said hub on the same plane with the pawl 31. A drivinggear 41 is rotatably mounted on said hub and held in frictionalengagement and rotatable therewith by means of friction washers 48 and49 which are anchored to said hub in order to rotate therewith.

The operation of said timing device will now be described, it beingunderstood that in its normal position, and when the winding lever is inthe position shown in Figure '7 of the drawings, the ratchet is in aposition rearward of the position in which it is shown in Figure 9 ofthe drawings. When the winding lever 33 is moved towards its startingposition, as shown'in Figure 9, the point 50 on the pawl 31 engages theback of the ratchet 46 and moves the ratchet to the position shown. Atthe same time, the lever 33 winds the main spring 29. The lever is nowin its starting position and, when released, the point 5| of the pawlwill engage the notch 52 of the ratchet, being forced into engagementtherewith by the spring 39. The said ratchet is now driven by theunwinding action of the main spring and the same, being rigidlyconnected to the hub 45 to which the friction washers 46 and 49 are alsorigidly connected, will drive the main gear 41 and thus operate theentire-timing mechanism.

The length of the timing period is controlled as follows:

The unwinding of the main spring 29 will tend to move the winding leverback to its normal position but this movement is delayed by the timingmechanism. When the timing period has elapsed, the roller 53, dependingfrom the pawl 31, will engage the surface of the cam 40 and cause thepawl to disengage from the ratchet. The lever 33 is thus released andthe same will snap back to its normal position releasing the remainingtension in the main spring 29 caused by the movement of lever 33 andthus terminating the time period and the operation of the timing device.It will be readily seen that the time period can, therefore, belengthened or shortened by manually setting the cam 40, thru the handle43, nearer or farther from the roller 53 when the lever 33, pawl 37 andratchet 46 are in the starting position of their driving operation. Thesame cam is retained in any position in which it is set by means of thetension washers 4| and 42 which are rigidly secured to the anchored stud3|.

As shown in the drawings, a lever 54 is pivoted at 55 to the housing 24.A roller 56 is mounted to the winding lever 33 by means of a stud 51 andextends thru a slot 58 in said lever 54 so that when the winding leveris released, at the end of a timing period, the said lever 54 will beoperated to separate the contacts 59 of an electric switch 22 byengaging the extension 60 of the switch bar 6| and thus cut 01! thesupply of electric current to the heating elements or when the operationof the timing device is started, the contacts 59' are brought together,by the tension of the spring 62 acting on the switch bar 6|, thusclosing the electric circuit and supplying current to the heatingelements during the internal of the timing period.

If desired, the operation of the said lever 54 may be applied to give as gnal at the expiration of the timing period by the use of a bellringing device clearly shown in Figure 4 of the drawings. This deviceconsists merely of a bell 63 which is mounted in place of the switch 22.A hammer is mounted on a bar 64 and pivoted as at 66 to a bracket 66 andretained in a position, away from said bell, by means of a spring 61which will tend to pull said bar against the stop 66. An extension 69 isprovided at the end of the bar 51 and is disposed in the path of thelever 54 so that when the said lever is operated, by the releasing ofthe winding lever 23, it will strike the said extension 62 and cause thehammer to ring the bell.

That part of the mechanism shown which .involves my invention will nowbe described:

An extension I0 is provided on the housing 24. This extension has aguide slot H therein thru which the lever 54 extends.

A heat responsive member, such as a bi-metallic thermostatic bar 12, ismounted on the floor 13 of one of the cooking chambers 6 by means of abracket 14. A stop member 15, having an inclined stop surface 16, isloosely mounted on said thermostatic bar by means of a slot therein thruwhich said bar extends. Said stop member extends thru a slot in thefloor 13, thru a guide slot in the portion ll of the extention Ill andpast the slot Ii so that the stop surface 16 thereof is disposed acrossthe said slot and in the path of the lever 54. An abutment I8 is formedin the portion TI to support the stop member I5 against ammvs motionwhen pressure is applied thereto by lever Bl.

The operation of the mechanism comprised in my invention is as follows:

Assuming that the electric toaster. as shown in the drawings, is in acold state and that a source of electric current is connected thereto bymeans of a plug which is attached to the terminal pin 20. when the firstcooking operation is to be performed therein, the bread supports areswung outwardly, a slice of bread is deposited on each the of saidsupports and they are then returned to the position shown in Figure 2 ofthe drawings. The winding handle 34 of the timing mechanism is now movedto the position shown in dotted lines of Figure 7 and released. Thismovement of the winding lever will swing the lever 54 against the stopsurface I6 of the stop member as shown clearly in Figure 5 of thedrawings. The stopping action on the lever 54 will limit the windingmovement of the lever 33. The movement of said lever 54 will cause theswitch bar extension 60 to be released by said lever and forced, bymeans of the spring 62, so that the contacts 59 will be-brought intoclosed position; thus closing the electric circuit thru said switch andheating the elements I. The timing device will operate, as abovedescribed, until the pawl 31 is disengaged from the ratchet 48 by meansof the cam at which time the lever 33 is released and will quickly moveto its normal position and operate the lever 54 to open the switch or,in the application shown in Figure 4 of the drawings, ring the bell andthe timing period for the cooking operation is terminated.

It will be readily understood that; as each succeeding cooking operationis performed in the cooking device, the temperature within the cookingchambers will naturally rise so that the succeeding cooking operationwill not require the same length of time period as the precedingoperation on account of the varying degree of temperature in the cookingchambers. As the temperature in the cooking chambers increases, thethermostatic bar 12 will flex downwardly, as shown in the drawings, thuslowering the stop member 15 and moving the stop surface thereon nearerto the lever 54 so that when the next cooking operation is performed,and the stop lever 54 is moved against the-said stop surface, it willbe'stopped at a point slightly ahead of the point where the said leverwas stopped in the preceding operation, when the temperature in thecooking chamber was lower, thus limiting the winding limit of thewinding lever 33 so that the ratchet 46 will come to a stop at aposition slightly nearer to the cam 40 and thus shortening the timeperiod.

If a delay should occur between the successive cooking operations, thetoaster will naturally tend to cool and the thermostatic bar will returntowards its normal position, raising the stop mem her, and lengtheningthe time period by permitting slightly further travel of the lever 54and consequently of the winding lever 33.

From the above description, it will be clearly understood that I haveprovided means whereby the time period provided by a clock mechanismwill be automatically varied, to'correspond to the temperature of acooking device, by thermostati- --ca.lly controlling the distancetraveled by said mechanism during the operation thereof by means ofregulating the degree to which the said clock mechanism is wound, andthus automatically varying the time period by controlling the startingpoint thereof with relation to a manually adjustable time periodterminating means.

While I have shown and described my invention as applied to thestructure illustrated in the drawings, it is desired to have itunderstood that the said invention may be applied to different forms oftiming devices which may be used in various types ofcooking deviceswithout departing from the scope of the invention as set forth in theappended claims.

The present application is a continuation of my application Serial No.745,968, filed September 28, 1934.

I claim:

1. An automatic toaster including an electric heating element, a controlswitch therefor biased to closed position and means for initiating andfor terminating a toasting operation, said means including a mechanicaltimer having a power spring and a retarding gear train, a pivotallymounted handle to which one end of said power spring is connected, saidhandle bei normally held by said power spring at one end of its path ofmovement and being actuatable away therefrom to wind said spring, aratchet frictionally connected with said gear train, a pawl mounted onand movable with said handle and normally biased into engagement withsaid ratchet, a lever arm connected with said handle and effective tohold said control switch in open position when the handle is at said oneend of its path of movement and a pawl release cam for effectingdisengagement of the pawl from the ratchet to cause quick returnmovement of said handle to its initial position and opening movement ofsaid control switch.

2. An automatic toaster including an electric heating element, a controlswitch therefor biased to closed position and means for initiating andfor terminating a toasting operation, said means including a mechanicaltimer having a power spring and a retarding gear train, a pivotallymounted handle to which one end of said power spring is connected, saidhandle being normally held by said power spring at one end of its pathof movement and being actuatable away therefrom to wind said spring, aratchet frictionally connected with said gear train, a pawl mounted onand movable with said handle and normally biased into engagement withsaid ratchet, a lever 0 by said lever arm during spring winding movementof said handle to limit its movement in a spring winding direction.

3. A device as set forth in claim 1 in which the pivotal mounting of thehandle is coaxial with the mounting of the ratchet, of the pawl releasecam and of the power spring.

4. An automatic toaster including an electric heating element, a controlswitch therefor biased to closed position and means including a singledirectly manually-actuatable pivotally-mounted lever arm for initiatingand for terminating a toasting operation, said means including further amechanical timer having a spring and a retarding gear train, one end ofsaid spring being connected with said pivotally mounted lever arm tocause winding up of the spring by movement of said lever arm in onedirection, a second pivotally mounted lever arm mechanically connectedwith said first named lever arm normally held in engagement with saidcontrol switch by said iii spring to hold said switch in open position,a ratchet mounted coaxially with said first named lever arm having afriction connection with said gear train, a pawl mounted on said firstnamed lever arm and engaging said ratchet to cause operation of saidgear train by said spring and a manually adjustable pawl release cam foroperatively engaging said pawl to disengage it from said ratchet andcause the power spring to move said control switch to its open positionunder full power of said spring.

5. An automatic toaster comprising an electric heating element, acontrol switch therefor biased to closed position, a mechanical timerhaving a power spring and a retarding gear train, a handle having oneend of said power spring connected therewith and normally held therebyin a limiting position, a lever having an operative conncction with saidhandle and normally operatively engaging said control switch to hold thelatter in open position, movement of said handle in a direction awayfrom said limiting position causing closing of said control switch andwinding of said power spring, the power spring then effectinggear-train-delayed return movement of said handle, a cam surface andmeans operatively associated with said handle for engaging said camsurface to cause disengagement of said handle and power spring from saidgear train with resultant quick movement of said handle to its limitingposition and opening of said control switch.

6. An automatic toaster comprising an electric heating element, acontrol switch therefor biased to closed position, a mechanical timerhaving a power spring and a retarding gear train, a handle having oneend of said power spring connected therewith, a lever arm-mechanicallyconnected with said handle engageable with said control switch andeffective to normally hold said switch in open position to thereby limitmovement of said handle in one direction, a pawl and ratchet connectionbetween said handle and said gear train to cause gear-train-de'layedreturn of said handle in said one direction after spring-windingmovement of said handle in the other direction and a manually-adjustablecam surface 0peratively engageable by said pawl to efiect disconnectionof said handle from said gear train to cause quick return of said handleto its switch opening position.

7. An automatic toaster comprising an electric heating element, acontrol switch therefor biased to closed position, a mechanical timerincluding a power spring, a retarding gear train and means operativelyconnecting said spring and gear train including ratchet, a pawl and afriction coupling, a pivotally mounted winding lever having one end ofthe power spring connected therewith and having the pawl mountedthereon, apivotally mounted lever arm connected with the winding leverto move therewith and normally operative to hold said control switch inopen position to limit spring-unwinding movement of said winding lever,spring-winding movement of said winding lever causing opening of saidcontrol switch, a thermally-controlled element having an -inclinedsurface adapted to be engaged by said lever arm during spring windingmovement of said winding lever to limit the winding of said spring and amanually adjustable cam operatively engageable by said pawl during thespring unwinding movement of said winding lever to cause disengagementof the winding lever and spring from said retarding gear train withconsequent quick return of the winding lever to its initial position andopening of said switch by said lever arm.

8. An automatic toaster comprising an electric heating element, acontrol switch therefor biased to closed position, a mechanical timerincluding a spring, a retarding gear train and means operativelyconnecting said spring and said gear train including a ratchet, a pawland a friction coupling, a Winding lever having one end of said springconnected therewith and having the pawl mounted thereon, meansactuatable by said winding lever to normally hold the switch in openposition, said last named means being effective to limit thespring-unwinding movement of said winding lever, a thermally controlledstop member engageable with said last named means for limiting thespring-winding movement of said winding lever and manually actuatablemeans for causing disengagement of the spring and winding lever from theretarding gear train for quick return of the winding lever to switchopening position under full power exertable by said spring,

9. A device as set forth in claim 7 in which the friction coupling,winding lever, manuallyadjustable cam and the ratchet are coaxiallymounted.

10. An automatic toaster comprising an electric heating element, acontrol switch therefor biased to closed position, a mechanical timerincluding a power spring, a retarding gear train and means operativelyconnecting said spring and said gear train including a ratchet, a pawland a friction coupling, a winding lever having one end of said powerspring connected therewith and having the pawl mounted thereon, meansactuatable by said winding lever to normally hold the switch in openposition, said last named means being effective to limit thespring-unwinding movement of said winding lever, a thermally controlledstop member engageable with said last named means for limiting thespring-winding movement of said winding lever and manually adjustablemeans operatively engageable by said pawl in its movement duringunwinding of the spring for effecting disengagement of said pawl fromsaid ratchet to thereby terminate a toasting operation.

11. An automatic toaster comprising an electric heating element, a.control switch therefor biased to closed position, a mechanical timerincluding a power spring, a retarding gear train and means operativelyconnecting said spring and said gear train including a ratchet, a pawland a friction coupling, a winding lever having one end of said powerspring connected therewith and having the pawl mounted thereon, meansactuatable by said winding lever to normally hold the switch in openposition, said last named means being eifective to limit thespring-unwinding movement of said winding lever, a thermally controlledstop member, engageable with said last named means for limiting thespring-winding movement of said winding lever and manually adjustablemeans including a cam mounted coaxially with said winding lever andoperatively engageable with said pawl to thereby cause termination of atoasting operation by opening of said switch.

12. An automatic toaster comprising an electric heating element, acontrol switch therefor biased to closed position, a mechanical timerincluding a power spring, a retarding gear train, a friction coupling, aratchet and a pawl, a winding lever supporting said pawl and mountedcoaxially with said power spring, said friction coupling and saidratchet, one end of said power spring being 15 directly connected tosaid winding lever, a lever arm having a pin and slot connection withsaid winding lever to be actuated thereby and normally held by saidpower spring in a position to hold said switch in open position,thermally controlled means engageable by said lever arm to limit thedegree of winding of said power spring and a manually adjustable cammounted coaxially with said winding lever and operatively engageablewith said pawl to effect disengagement of said power spring and windinglever from said gear train to thereby cause quick movement of said leverarm to its switch opening position.

13. An automatic toaster including an electric heating means, a controlswitch for said heatin means biased to closed position, means toinitiate a toasting operation and means to terminate a toastingoperation, said terminating means comprising a mechanical timer having apower spring and a retarding gear train, means operatively connectingsaid power spring and said control switch to normally hold said switchin open position and movable in one direction to wind up said powerspring and cause closing of said switch and manually adjustable meansfor effecting disconnection of said power spring from said gear trainduring unwinding movement of said power spring to cause quick returnmovement of said means operatively connecting the power spring and saidcontrol switch and quick opening of said control switch.

14. An automatic toaster comprising an electric heating element, acontrol switch therefor biased to closed position, a mechanical timerhaving a power spring and a retarding gear train, a handle pivotallymounted for rotative movement connected to said power spring andnormally held thereby at one end of its rotative movement, a pivotallymounted lever arm operatively connected with said handle and normallyheld by said power spring in operative engagement with said controlswitch to hold the latter in open position, rotative movement of saidhandle away from said end position causing disengagement of said leverarm from said control switch and winding of said power spring, the powerspring, on release of said handle, effecting gear-traindelayed returnrotary movement of said handle, a manually adjustable cam andmeansoperatively associated and movable with said handle for engagingsaid cam to effect disengagement of said handle and said power springfrom said gear train to cause the power spring to move said handlequickly to said end position and quick opening of said control switch.

LOUIS V. LUCIA.

